Comoving cooling rates of different cooling mechanisms for the electrons with the energy distribution presented in Figure 1. Different colors (red, green, and blue) denote the cooling rates at different epochs, and different line styles (solid, dashed, and dotted) present different cooling mechanisms (SSC, synchrotron, and adiabatic). Note that in M1, synchrotron cooling rates are time-independent, since ﹩{B}^{{\prime} }﹩ is a constant in this case.